The Kings of Connacht were rulers of the cóiced (variously translated as portion, fifth, province) of Connacht, which lies west of the River Shannon, Ireland. However, the name only became applied to it in the early medieval era, being named after the Connachta.

The old name for the province was Cóiced Ol nEchmacht (the fifth of the Ol nEchmacht). Ptolemy's map of c. 150 AD does in fact list a people called the Nagnatae as living in the west of Ireland. Some are of the opinion that Ptolemy's Map of Ireland may be based on cartography carried out as much as five hundred years before his time.

The Connachta were a group of dynasties who claimed descent from the three eldest sons of Eochaid Mugmedon: Brion, Ailill and Fiachrae. They took their collective name from their alleged descent from Conn Cétchathach. Their younger brother, Niall Noigiallach was ancestor to the Uí Néill.

The following is a list of kings of Connacht from the fifth to fifteenth centuries.

• Genann
• Conrac Cas
• Eochaid Feidlech
• Eochaidh Allat
• Tinni mac Conri
• Medb, Queen of Connacht
• Medb and Ailill mac Máta
• Maine Aithreamhail mac Ailill Máta
• Sanbh Sithcheann mac Ceat mac Magha
• Cairbre mac Maine Aithreamhail
• Eochaidh Fionn
• Aodh mac Cu Odhar
• Eochaidh mac Cairbre
• Aonghus Fionn mac Domhnall
• Cormac Ulfhada
• Aonghus Feirt mac Aonghus Fionn
• Connall Cruchain mac Aonghus Feirt
• Fearadach mac Connal Cruchain
• Forghus Fiansa
• Forghus Fiansa and Art mac Conn
• Ceidghin Cruchain mac Connall Cruchain
• Aodh mac Eochaidh
• Aodh Alainn mac Eochaidh Baicidh
• Nia Mór mac Lughna
• Lughaidh mac Lughna Fear Tri
• Aodh Caomh mac Garadh Glundubh
• Coinne mac Fear Tri
• Muireadh Tireach mac Fiachra Sraibrintne
• Eochaid Mugmedon
• Niall Noigiallach/Niall of the Nine Hostages, died c. 450/455

• List of High Kings of Ireland
• List of kings of Ulster
• List of kings of Leinster
• List of kings of Munster
• List of kings of Mide

• Annals of the Four Masters, 1990 edition.
• The Annals of Connacht, A. Martin Freeman, 1944.
• Irish Kings and High Kings, Francis John Byrne, 1973.
• Leabhar Mor Genealach, Dubhaltach MacFhirbhisigh, ed. O'Muralie, 2004.

• Ó Conchobair and Burke at The Irish Story
• A Poem on the Kings of Connacht^{[permanent dead link]}